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Re: Cursor position on images

  • To: mathgroup at smc.vnet.net
  • Subject: [mg129397] Re: Cursor position on images
  • From: "King, Peter R" <peter.king at imperial.ac.uk>
  • Date: Thu, 10 Jan 2013 21:40:57 -0500 (EST)
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I have a much bigger problem in that when I try this I just get a red rectangle with the error message "Image is not a graphics primitive or directive".

I am using Mathematica 7 so is there a difference between how Mathematica treats images/graphics objects in this version compared with later versions and how do I rectify this?

Thanks,

Peter

-----Original Message-----
From: mathgroup-adm at smc.vnet.net [mailto:mathgroup-adm at smc.vnet.net] On Behalf Of Murray Eisenberg
Sent: 10 January 2013 07:22
To: mathgroup at smc.vnet.net
Subject: [mg129397] Re: Cursor position on images

I discovered the source of the problem: on Mac OS X it's Command + Click instead of Alt + Click!

And in the Documentation Center, e.g., ref/LocatorAutoCreate, it incorrectly and repeatedly gives Alt + Click, which is OK for Windows, but should be instead Command + Click for OS X.


On Jan 9, 2013, at 9:16 AM, Murray Eisenberg <murray at math.umass.edu> wrote:

> I still don't quite understand.
>
> In your original message, you included the following steps:
>
>  Step 2: Enter the reference points at the plot axes into the input fields. Press Enter.
>
>  Step3: Alt+Click on the point with x-coordinate x1.
>         This brings up the first locator visible as a circle.
>         Alt+Click on that with x2 which gives rise to the second locator.
>         Adjust the locators, if necessary.
>         Press the button ?Memorize scale X?.
>
> I think you're now saying to do things in an opposite order:
>
>  (1) first put 2 by Alt+MouseClick put locators in two positions along, say, the x axis,
>  (2) type two corresponding x coordinates and
>  (3) then press the button "Memorize scale x",
>  (4) then pull the same locators in two points along the y axis,
>  (5) type the corresponding y values and
>  (6) press the corresponding button.
>
> I presume this new (1) has a typo and should be simply:
>
>   (1) first put Alt+MouseClick put locators in two positions along, say, the x axis,
>
> Assuming this new, opposite, order is what you intended,
>
> Still, no locator appears when I Alt-click anywhere in the image output after the copyCurve[pic] is evaluated. That's using Mathematica 9.0.0 under Mac OS X 10.8.2.
>
> I now tried the same thing, with the same image, using the Windows version of Mathematica 9.0.0 under Windows 7 (running in a virtual machine in Parallels Desktop 8 on my same Mac). Now copyCurve _does_ work.
>
> So something's wrong with copyCurve on Mac. (Of course Alt in the Mac context means Option.) I tried the "obvious" things of Alt+Shift+Click, but that still does not produce a Locator.
>
> Wait=85the problem is with Alt-Click in Mathematica under OS X, for anything! For example, the code
>
>  Manipulate[
>     Graphics[{Line[u]}, PlotRange -> 2], {{u, {{-1, -1}, {1, 1}}},
>     Locator, LocatorAutoCreate -> True}]
>
> from the Documentation Center does not work as expected in OS X: using =
Alt-Click does not create a new Locator!
>
> [In your original message, you partially reversed steps (1) and (2). There you said
> On Jan 9, 2013, at 3:33 AM, Alexei Boulbitch <Alexei.Boulbitch at iee.lu> =
wrote:
>
>> Dear Murray,
>>
>> In principle this:
>> pic = ExampleData[{"TestImage", "Lena"}]
>>  copyCurve[pic]
>> is exactly how it should be used. I could not, however, repeat =
ExampleData[{"TestImage", "Lena"}] on my machine. It did not load the =
image for a long time, and after 5 minutes waiting I aborted it and =
copy-pasted Lena from Menu/Help/Image. I tried on my machine (Math9, PC, =
=
Win XP) with Lena obtained this way and it works. It is only necessary =
that the graphics you use has the head Image. Otherwise you can wrap it =
with Image.  It also worked for me with PC/XP/Math8 (in which I have =
written it) and on PC/Win.7/Math9. I never tried it on Mac though.
>>
>> A minor thing is not quite correct with your sequence of actions. You =
=
should first put 2 by Alt+MouseClick put locators in two positions =
along, say, the x axis, type two corresponding x coordinates and then =
press the button "Memorize scale x", then pull the same locators in two =
points along the y axis, type the corresponding y values and press the =
corresponding button. Then use the same 2 locators at the first 2 points =
=
of the line you need to digitalize and add more locators where needed. =
The order x before y or y before x is of no importance. But of course, =
as soon as locators show up you immediately find the right way.
>>
>> Did you try to change the colour of the locators by the ColorSlider? =
They are red by default and may be poorly visible with Lena on the =
background.
>>
>> Best, Alexei
>>
>> Alexei BOULBITCH, Dr., habil.
>> IEE S.A.
>> ZAE Weiergewan,
>> 11, rue Edmond Reuter,
>> L-5326 Contern, LUXEMBOURG
>>
>> Office phone :  +352-2454-2566
>> Office fax:       +352-2454-3566
>> mobile phone:  +49 151 52 40 66 44
>>
>> e-mail: alexei.boulbitch at iee.lu
>>
>>
>> -----Original Message-----
>> From: Murray Eisenberg [mailto:murray at math.umass.edu]
>> Sent: Tuesday, January 08, 2013 6:16 PM
>> To: mathgroup
>> Subject: Re: Cursor position on images
>>
>> Either I'm not understanding the instructions for copyCurve or else =
something is not working right for Mathematica 9.0.0 on Mac OS X. =
Example:
>>
>>  pic = ExampleData[{"TestImage", "Lena"}]
>>  copyCurve[pic]
>>
>> I now type into the x1, y1, x2, y2 input fields the values 0, 0, 200, =
=
200 respectively and press Enter.
>>
>> When I use Alt+Click, nothing happens -- I don't see any Locator.
>>
>> I also tried Shift+Alt+Click in case that's required for Mac, but =
still no action.
>>
>> On Jan 7, 2013, at 11:07 PM, Alexei Boulbitch =
<Alexei.Boulbitch at iee.lu> wrote:
>>
>>> I am sure this is straightforward but I cannot quite see how to do =
this. I have an image (jpg file, but could be any format if that =
matters). I want to be able to left click on the image and mark the =
point with a dot of some sort and collect the coordinates of the point =
(the coordinate system is fairly arbitrary). I then want to be able to =
repeat this as many times as required and end up with a list of the =
coordinates of the points clicked on for further manipulation. Clickpane =
=
should do the trick but I can't work out how.
>>>
>>> Any suggestions, thanks.
>>>
>>> Peter
>>>
>>> Hi, Peter,
>>>
>>> It is not exactly but very close to what you ask about. Below you =
will find a function along with its description. I use it to digitalize  =
=
functions only available as curves on graphics, like taken from images. =
This might be what you have in mind. To try it just copy-paste any image =
=
into Mathematica, give it a name and apply the copyCurve function to it. =
=
Then act as it is described below. As the result you will get a list of =
points coordinates.
>>>
>>> Have fun, Alexei
>>>
>>>
>>>
>>> Description
>>>
>>> The function copyCurve enables one to get the coordinates of curve =
points from a plot found on an image and memorises them in a list =
entitled ?listOfPoints?
>>> Parameters:
>>>
>>> image is any image. It should have Head=Image, but may be also a =
Graphics object, since no specific functions of image have been used. I =
typically wrap it in Image[] statement.
>>>
>>> Controls:
>>>
>>> The Checkbox ?whiteLocatorRing? defines, if the locators are shown =
by a single color ring (unchecked), or with two rings, the outer having =
a color defined by the ColorSlider (see below), the innder being white. =
This may be helpful, if working with a too dark image.
>>>
>>> size controls the size of the image. The default value is 450. This =
slider is used to adjust the size to the one to enable the most =
comfortable work with the image plot.
>>>
>>> opacity controls the opacity of the line connecting the locators
>>>
>>> thickness controls the thickness of the double ring that forms each =
locator.
>>>
>>> lineThickness controls the thickness of the line connecting the =
locators
>>>
>>> color is the color slider that controls the color of the outer ring =
forming the locator and the line connecting them. The inned locator ring =
=
is always white.
>>>
>>> radius controls the radius of the locators.
>>>
>>> InputFields: should be supplied by the reference points x1 and x2 at =
=
the axis x, as well as y1 and y2 at the axis y.
>>>
>>> Buttons: The buttons ?Memorize scale X? and ?Memorize scale Y? =
should be pressed after the first two locators are placed on the =
corresponding reference points (presumably, located at the x or y axes). =
=
Upon pressing the reference points are memorized. The button ?Make list =
of the curve points? should be pressed at the end of the session. Upon =
its pressing the actual list of points representing the points of the =
curve is assigned to the global variable ?listOfPoints?
>>>
>>>
>>> Operation:
>>> Step 1: Execute the function with the name of the image containing =
the curve to be digitalized.
>>>
>>> Step 2: Enter the reference points at the plot axes into the input =
fields. Press Enter.
>>>
>>> Step3: Alt+Click on the point with x-coordinate x1. This brings up =
the first locator visible as a circle. Alt+Click on that with x2 which =
gives rise to the second locator. Adjust the locators, if necessary. =
Press the button ?Memorize scale X?.
>>>
>>> Step 4: Move the two already existing locators to the points with =
the coordinates y1 and y2. Press the button ?Memorize scale Y?. Now the =
both scales are captured.
>>>
>>> Step 5: Move the two already existing locators to the first two =
points of the curve to be captured. Alt+Click on other points of the =
curve. Each Alt+Click will generate an additional locator. Adjust =
locators, if necessary. To remove,  Alt+Click on unnecessary locators.
>>>
>>> Step 6: Press the button ?Make the list...?. This assigns the =
captured list to the variable ?listOfPoints?. Done.
>>>
>>> The ?listOfPoints? is a global variable. It can be addressed =
everywhere in the notebook.
>>>
>>> The function copyCurve
>>>
>>> Clear[copyCurve];
>>>
>>> copyCurve[image_] :=
>>>
>>> Manipulate[
>>> DynamicModule[{pts = {}, x1 = Null, x2 = Null, y1 = Null,
>>>   y2 = Null, X1, X2, Y1, Y2, \[CapitalDelta]X, \[CapitalDelta]Y, =
g,
>>>    myRound},
>>>
>>>  myRound[x_] := Round[1000.*x]/1000. // N;
>>>
>>>  (* Begins the column with all the content of the manipulate *)
>>>  Column[{
>>>    (* Begin LocatorPane*)
>>>    Dynamic@LocatorPane[Union[Dynamic[pts]],
>>>      Dynamic@
>>>       Show[{ReplacePart[image, {4, 2} -> size],
>>>         Graphics[{color, AbsoluteThickness[lineThickness],
>>>           Opacity[opacity], Line[Union[pts]]}]
>>>             }], LocatorAutoCreate -> True,
>>>      (* Begin Locator appearance *)
>>>      Appearance -> If[whiteLocatorRing,
>>>
>>>        Graphics[{{color, AbsoluteThickness[thickness],
>>>           Circle[{0, 0}, radius + thickness/2]}, {White,
>>>           AbsoluteThickness[thickness], Circle[{0, 0}, radius]}},
>>>         ImageSize -> 10]
>>>        ,
>>>        Graphics[{{color, AbsoluteThickness[thickness],
>>>           Circle[{0, 0}, radius + thickness/2]}},
>>>         ImageSize -> 10]](* End Locator appearance *)
>>>                            ],(* End LocatorPane*)
>>>
>>>    (* Begin of the block of InputFields *)
>>>    , Row[{ Style["\!\(\*SubscriptBox[\(x\), \(1\)]\):"],
>>>      InputField[Dynamic[x1],
>>>       FieldHint -> "Type  \!\(\*SubscriptBox[\(x\), \(1\)]\)",
>>>       FieldSize -> 7, FieldHintStyle -> {Red}],
>>>      Spacer[20], Style["   \!\(\*SubscriptBox[\(y\), \(1\)]\):"],
>>>      InputField[Dynamic[y1],
>>>       FieldHint -> "Type  \!\(\*SubscriptBox[\(y\), \(1\)]\)",
>>>       FieldSize -> 7, FieldHintStyle -> {Red}]
>>>             }],
>>>    Row[{ Style["\!\(\*SubscriptBox[\(x\), \(2\)]\):"],
>>>      InputField[Dynamic[x2],
>>>       FieldHint -> "Type \!\(\*SubscriptBox[\(x\), \(2\)]\)",
>>>       FieldSize -> 7, FieldHintStyle -> {Red}],
>>>      Spacer[20], Style["   \!\(\*SubscriptBox[\(y\), \(2\)]\):"],
>>>      InputField[Dynamic[y2],
>>>       FieldHint ->
>>>        "Type  \!\(\*SubscriptBox[\(y\), \(2\)]\)+Enter",
>>>       FieldSize -> 7, FieldHintStyle -> {Red}]
>>>             }],
>>>    (* End of the block of InputFields *)
>>>    (* Begin the buttons row *)
>>>    Row[{Spacer[15],
>>>      (* Begin button "Memorize scale X" *)
>>>      Button["Memorize scale X",
>>>       X1 = Min[Transpose[myRound /@ Union[pts]][[1]]];
>>>       X2 = Max[Transpose[myRound /@ Union[pts]][[1]]];
>>>       \[CapitalDelta]X = X2 - X1;
>>>       ],(* End of button "Memorize scale X" *)
>>>      Spacer[70],
>>>      (* Begin button "Memorize scale Y" *)
>>>      Button["Memorize scale Y",
>>>       Y1 = Min[Transpose[myRound /@ Union[pts]][[2]]];
>>>       Y2 = Max[Transpose[myRound /@ Union[pts]][[2]]];
>>>       \[CapitalDelta]Y = Y2 - Y1;
>>>       ](* End of button "Memorize scale Y" *)
>>>
>>>
>>>      }],(* End the buttons row *)
>>>    Spacer[0],
>>>
>>>    (* Begin button "Make the list of the curve's points" *)
>>>    Button[Style["Make the list of the curve's points" , Bold],
>>>     g[{a_, b_}] := {(x1*X2 - x2*X1)/\[CapitalDelta]X +
>>>        a/\[CapitalDelta]X*Abs[x2 - x1], (
>>>        y1*Y2 - y2*Y1)/\[CapitalDelta]Y +
>>>        b/\[CapitalDelta]Y*Abs[y2 - y1]};
>>>     Clear[listOfPoints];
>>>     listOfPoints = Map[myRound, Map[g, pts]]
>>>                 ](* End of button "Make the list..." *)
>>>
>>>    }, Alignment -> Center](*
>>>  End of column with all the content of the manipulate *)
>>>  ],(* End of the DynamicModule *)
>>>
>>> (* The massive of sliders  begins *)
>>> Column[{Row[{Control[{whiteLocatorRing, {True, False}}],
>>>     Spacer[50]}],
>>>   Row[{Spacer[32.35], Control[{{size, 450}, 300, 800}],
>>>     Spacer[38.5`], Control[{{opacity, 0.5}, 0, 1}]}],
>>>   Row[{Spacer[10.], Control[{{thickness, 1}, 0.5, 5}],
>>>     Spacer[13.65], Control[{{lineThickness, 1}, 0, 10}] }],
>>>   Row[{Spacer[22.8], Control[{color, Red}], Spacer[59.3],
>>>     Control[{{radius, 0.5}, 0, 3}]}]
>>>   }, Alignment -> Center],(* The massive of sliders ends *)
>>>
>>> (* Definitions of sliders *)
>>> ControlType -> {Checkbox, Slider, Slider, Slider, Slider,
>>>   ColorSlider, Slider},
>>> ControlPlacement -> Top, SaveDefinitions -> True
>>> ];
>>> (* End of the function *)
>>>
>>>
>>> Alexei BOULBITCH, Dr., habil.
>>> IEE S.A.
>>> ZAE Weiergewan,
>>> 11, rue Edmond Reuter,
>>> L-5326 Contern, LUXEMBOURG
>>>
>>> Office phone :  +352-2454-2566
>>> Office fax:       +352-2454-3566
>>> mobile phone:  +49 151 52 40 66 44
>>>
>>> e-mail: alexei.boulbitch at iee.lu
>>
>> ---
>> Murray Eisenberg                                    =
murray at math.umass.edu
>> Mathematics & Statistics Dept.     
>> Lederle Graduate Research Tower            phone 413 549-1020 (H)
>> University of Massachusetts                               413 =
545-2838 (W)
>> 710 North Pleasant Street                         fax   413 545-1801
>> Amherst, MA 01003-9305
>>
>>
>>
>>
>>
>>
>
> ---
> Murray Eisenberg                                    =
murray at math.umass.edu
> Mathematics & Statistics Dept.     
> Lederle Graduate Research Tower            phone 413 549-1020 (H)
> University of Massachusetts                               413 545-2838 =
=
(W)
> 710 North Pleasant Street                         fax   413 545-1801
> Amherst, MA 01003-9305
>
>
>
>
>

---
Murray Eisenberg                                    =
murray at math.umass.edu
Mathematics & Statistics Dept.     
Lederle Graduate Research Tower            phone 413 549-1020 (H)
University of Massachusetts                               413 545-2838 =
(W)
710 North Pleasant Street                         fax   413 545-1801
Amherst, MA 01003-9305









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